1. Field of the Invention
The invention relates to foaming compositions for cleaning the skin which preferably are rich in oils, gelled in appearance, transparent and water-rinsable.
2. Discussion of the Background
Cleaning the skin is very important for face care. It must be as effective as possible because the fatty residues such as excess sebum, residues of the cosmetic products which are employed daily, and make-up products, especially the water-resistant "waterproof" products, accumulate in skin folds and at the surface of the skin and can block skin pores and entail the appearance of spots. Poor cleaning quality, and in particular poor rinsing, are often responsible, among other causative factors, for a sallow complexion.
A number of major types of products for cleaning the skin are known: lotions and foaming detergent aqueous gels and oils and rinsable cleaning anhydrous gels, milks for removing make-up, and foaming creams which are usually soap-based.
The lotions and the foaming detergent aqueous gels have a cleaning action by virtue of the surfactants which place the fatty residues and the pigments of the make-up products in suspension. They are effective and cosmetically pleasant because they foam and because they are easily removed. Insofar as they do not contain any cosmetic oil, they have the disadvantage of making the skin dry owing to their lipid-removing action.
This is the case, for example, with the products described by document WO 95/05769, which teaches lotions for cleaning the skin, which are very fluid, pressurizable and which produce a beautiful foam, but these products destroy the hydrolipid film of the skin and leave the skin clean but rough.
The creams and the milks for removing make-up contain, at the same time, oils, emulsifiers and detergent surfactants in a quantity which is sufficiently low not to destabilize the emulsion. Despite their good effectiveness, these products are not foaming and have an insufficient rinsability which requires the use of a complementary detergent tonic lotion to complete the rinsing and the removal of the soiling. Besides its astringent character, the use of this second product can in the long term result in making the skin dry.
In the field of skin cleaning, the removal of make-up of water-resistant "waterproof" products, of transfer-free products and of heavy make-ups, like stage make-ups, requires the use of oily compounds to be effective.
Oily compositions are recognized for their effectiveness as a cleaning agent and/or make-up remover. They in fact allow lipophilic soiling and make-up to be dissolved very easily, in particular the "waterproof" and transfer-free make-ups which are known to be difficult to remove. These products are effective and well tolerated. They have the disadvantage of not foaming and not imparting a feeling of coolness on application, and this is a disadvantage from a cosmetic viewpoint. Besides, the oily compositions which have the appearance of a gel are usually thickened with waxes, silicas, modified clays or polyvalent salts of fatty acids, which give them an appearance that is usually turbid or opaque and not very attractive; their stability over time is often limited.
Attempts have been made to design cleaning foaming products which are perfectly rinsable with water, including oils in large quantities so as to optimize the cleaning of the skin and to hydrate and nourish the latter while avoiding any phenomenon of drying out and of irritation. In addition, attempts have been made to prepare compositions which have an attractive appearance, that of a transparent gel, these compositions being easily removed by rinsing with water and being perfectly stable in storage.
To produce such a product it is not possible merely to introduce oils into a lotion or an aqueous gel. In fact, oils have a tendency to inhibit the foaming properties of these formulations; it is said that the oils "kill" the foam.